Fix InvalidCastException triggered by non-string group keys

src/Seq.App.Slack/Messages/AlertV2MessageBuilder.cs

@@ -125,16 +125,23 @@ ce is IEnumerable<object?> contributingEvents &&
                 var text = new StringBuilder();
                 foreach (var contributing in contributingEvents.Skip(1).Cast<IEnumerable<object?>>())
                 {
-                    var columns = contributing.Cast<string>().ToArray();
+                    var columns = contributing.ToArray();
+
+                    const int contributingEventsIdIndex = 0,
+                        contributingEventsTimestampIndex = 1,
+                        contributingEventsMessageIndex = 2;
 
                     // Timestamp as ISO-8601 string
-                    text.Append(SlackSyntax.Code(columns[1]));
+                    text.Append(SlackSyntax.Code(columns[contributingEventsTimestampIndex] as string ?? ""));
                     text.Append(' ');
 
                     // Message, linking to event
-                    text.Append(SlackSyntax.Hyperlink(EventFormatting.LinkToId(_host, columns[0]),
-                        SlackSyntax.Escape(columns[2])));
+                    text.Append(SlackSyntax.Hyperlink(EventFormatting.LinkToId(_host, columns[contributingEventsIdIndex] as string ?? ""),
+                        SlackSyntax.Escape(columns[contributingEventsMessageIndex] as string ?? "")));
                     text.Append('\n');
+
+                    // Group key values currently ignored, they're included in Results. Some additional formatting
+                    // work would be needed if we were to add them here.
                 }
 
                 var events = new SlackMessageAttachment(color, text.ToString(), "Contributing Events");

src/Seq.App.Slack/Seq.App.Slack.csproj

@@ -2,7 +2,7 @@
 
     <PropertyGroup>
         <TargetFramework>net8.0</TargetFramework>
-        <VersionPrefix>2.0.0</VersionPrefix>
+        <VersionPrefix>2.0.1</VersionPrefix>
         <Description>An app for Seq that forwards events and notifications to Slack.</Description>
         <Authors>bytenik, Datalust, and Contributors</Authors>
         <PackageTags>seq-app</PackageTags>